An unexpected error has occurred. Yep. Very helpful! Recently, when attempting to use the Manage Content and Structure tool (found under Site Actions > Manage Content and Structure), I received the above error. Looking into the ULS logs, all I was able to get ahold of was a System.NullReferenceException. Again, not really handy, or useful, at all.

I was able to determine that it had to probably be due to a list… turns out, we had deactivated and retracted several features from our farm recently, several of which relied on custom lists to store the data. If I go to View All Site Content (Site Actions > View All Site Content), and click on one of these lists, I get a similar error to the above.

Luckily, one of the times when attempting to launch the Manage Content and Structure Tool, I was able to get this error in the ULS logs.

Failed to determine the setup path of the list schema for feature {553B9E4F-C7EA-4442-845F-94390C1EAE44}, list template 10000.

So, basically, we need to remove these lists. We cannot get into the “Delete this List” option within the List management screen – otherwise you’ll get an error similar to the above. I also attempted to use SharePoint Manager 2010, which also gave an error. I just couldn’t delete the list using traditional means…

You have two options here…

Write some code to delete the list (C#, PowerShell… whatever you desire)